A geodesic, the shortest path between two points in a mathematical space. Early urban cybernetic interfaces imparted this machine intelligence to citizens via origin-destination matrices placed at public transport nodes, introducing graph theoretic concepts to the urban masses. This TfL Journey Planner (1963) consists of separate origin and destination button matrices with a CRT monitor in the center. The machine communicates the shortest path between any two selected nodes.

A cybernetic form of urban mobility was born, a citizen’s behaviour increasingly expected to approximate the ‘rational agent’ used in urban computer models of the era.